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11.
Native genomic blotting: high-resolution mapping of DNase I-hypersensitive sites and protein-DNA interactions. 总被引:3,自引:1,他引:2 下载免费PDF全文
U Pauli S Chrysogelos J Stein G Stein 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(1):16-20
DNase I-hypersensitive sites are observed in the promoter regions of actively expressed genes, potentially active genes, and genes that were once active. We have developed an approach that greatly increases the resolution for mapping these sites by electrophoresing genomic DNA on native polyacrylamide gels prior to electroblotting and hybridization. This improved method has been used to scan the promoter and coding region of a cell-cycle-dependent human histone H4 gene with an accuracy of +/-5-10 base pairs. Protein-DNA interactions can be seen in the autoradiograph as light areas and DNase I-hypersensitive sites as dark bands. Therefore, this method provides a rapid and relatively simple means to accurately localize protein-DNA interactions as well as DNase I-hypersensitive sites, thus directly displaying DNase I hypersensitivity and protein-DNA complexes on one autoradiograph. It also potentially allows the analysis of small changes in DNase I-hypersensitive sites under various biological conditions. With this technique rather large regions of DNA can be screened to determine areas that should be analyzed by more sophisticated methods, such as genomic sequencing or gel retardation assays. 相似文献
12.
Anders Persson Stefan Pauli Christer Halldin Sharon Stone-Elander Lars Farde Irene Sjgren Gran Sedvall 《Human psychopharmacology》1989,4(1):21-31
The 11C-labelled benzodiazepine antagonist Ro 15–1788 (flumazenil) and positron emission tomography (PET) were used to determine quantitative characteristics of benzodiazepine receptor binding in the neocortex of healthy young men. Saturating doses of unlabelled flumazenil administered i.v., before or together with the ligand-reduced 11C-flumazenil accumulation in the neocortex by about 90 per cent. Saturating doses of unlabelled flumazenil had little effect on the accumulation of radioactivity in the benzodiazepine receptor-poor regions such as pons or white matter. By giving graded doses of unlabelled flumazenil together with the tracer, saturation isotherms were obtained allowing the calculation of receptor density (Bmax) and equilibrium dissociation constant (Kd) values on the basis of certain assumptions Bmax values were in the order of 90 pmol/g and Kd values in the order of 10 nM in the neocortex. Scatchard and Hill plots of the radioactivity data indicated that 11C-flumazenil binds to saturable sites of a homogeneous population. The data indicate that intravenous doses of 1 or 2 mg flumazenil result in a benzodiazepine receptor occupancy of about 50 per cent. The method described should be useful for studying regional differences in benzodiazepine receptor characteristics in the living human brain in healthy subjects and neuropsychiatric disorders, and also in relation to treatment with drugs interacting with benzodiazepine receptors. 相似文献
13.
C. Sohy F. Pons A. Casset M.-P. Chesnard F. Lieutier-Colas P. Meyer G. Pauli F. de Blay 《Clinical and experimental allergy》2006,36(6):795-802
BACKGROUND: Endotoxin was proposed to increase the severity of asthma. Endotoxin levels greatly differ according to settings. In domestic environments, airborne concentrations may be dramatically low compared with levels reported in occupational settings. OBJECTIVE: Our first objective was therefore to assess the effect of inhalation of low-level lipopolysaccharide (LPS) on the immediate and late-phase asthmatic bronchial response. Our second objective was to evaluate the effect of exposure to LPS on the local and systemic inflammatory response. METHODS: Nineteen asthmatics sensitized to cat underwent on two separate occasions a bronchial challenge test to cat allergen (cat BCT) preceded randomly by a pre-exposure to either saline or LPS (2 microg). Methacholine challenge test was performed 24 h before exposure to LPS or saline. The Borg scale for dyspnoea and lung function were recorded before and after exposure to LPS or saline, and before and after cat BCT. Induced sputum and blood samples were collected before and after cat BCT, and analysed for cell counts and eosinophil cationic protein (ECP) levels. RESULTS: Inhalation of 2 microg LPS did not induce any changes in forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), FEF 25-75 and Borg scale of dyspnoea. It neither modified Fel d 1 PD20 (45.03 ng as compared with 87.03; P=0.42). As well, there was no significant difference in late-phase reaction. Pre-exposure to LPS did not influence eosinophil counts or ECP levels in blood and sputum. CONCLUSION: Our study demonstrated that pre-exposure to LPS at low levels, which may be encountered in domestic environment, had no significant effect on the immediate and late-phase bronchial response to cat allergen. It neither modified local and systemic eosinophilic inflammation. 相似文献
14.
Cardiovascular malformations and organic solvent exposure during pregnancy in Finland 总被引:2,自引:0,他引:2
In order to investigate the possible association between cardiovascular malformations and maternal exposure to organic solvents during the first trimester of pregnancy, 569 cases and 1,052 controls were retrospectively studied. The cases represented all infants with diagnosed cardiovascular malformations born in Finland in 1982-1984, and the controls were randomly selected from all normal births in the country during the same period. All mothers were interviewed approximately 3 months after delivery by a midwife using a structured questionnaire. Exposures to organic solvents at work during the first trimester of pregnancy were slightly more prevalent among the mothers of affected infants (10.4%) than among those of controls (7.8%). Logistic regression analysis of exposure to organic solvents showed an adjusted relative odds ratio of 1.3 (95% confidence interval, 0.8-2.2). In the analysis of ventricular septal defect, exposure to organic solvents showed an adjusted relative odds ratio of 1.5 (95% confidence interval, 1.0-3.7). 相似文献
15.
16.
The metabolic fate of the benzodiazepine antagonist RO 15-1788 labelled with 11C was studied in plasma from human subjects after intravenous administration in connection with positron emission tomography. Ro 15–1788 and its metabolites were separated by thin-layer chromatography and the radioactivity in the different compounds was determined. 11C-Ro 15–1788 was extensively and rapidly metabolised to the corresponding free acid. At 36 minutes after administration only 50% of the radioactivity in plasma represented unchanged compound. 相似文献
17.
18.
Carol J. Ludowese Kate J. Thompson Gurbax S. Sekhon Richard M. Pauli 《Clinical genetics》1991,40(3):194-201
We describe ten individuals with an insertional duplication 15q12----q13. Phenotypic analysis of these individuals and 15 previously reported cases of proximal 15q duplications fails to show any consistent clinical manifestations. It appears that a duplication of this region is phenotypically silent. 相似文献
19.
Christian Foged Christer Halldin Christian Loc’h Bernard Mazière Stefan Pauli Mariannick Maziére Holger C. Hansen Tetsuya Suhara Carl-Gunnar Swahn Per Karlsson Lars Farde 《European journal of nuclear medicine and molecular imaging》1997,24(10):1261-1267
NNC 13-8241 has recently been labelled with iodine-123 and developed as a metabolically stable benzodiazepine receptor ligand
for single-photon emission computed tomography (SPECT) in monkeys and man. NNC 13-8199 is a bromo-analogue of NNC 13-8241.
This partial agonist binds selectively and with subnanomolar affinity to the benzodiazepine receptors. We prepared 76Br labelled NNC 13-8199 from the trimethyltin precursor by the chloramine-T method. Carbon-11 labelled NNC 13-8199 was synthesised
by N-alkylation of the nitrogen of the amide group with [11C]methyl iodide. Positron emission tomography (PET) examination with the two radioligands in monkeys demonstrated a high uptake
of radioactivity in the occipital, temporal and frontal cortex. In the study with [76Br]NNC 13-8199, the monkey brain uptake continued to increase until the time of displacement with flumazenil at 215 min after
injection. For both radioligands the radioactivity in the cortical brain regions was markedly reduced after displacement with
flumazenil. More than 98% of the radioactivity in monkey plasma represented unchanged radioligand 40 min after injection.
The low degree of metabolism indicates that NNC 13-8199 is metabolically much more stable than hitherto developed PET radioligands
for imaging of benzodiazepine receptors in the primate brain. [76Br]NNC 13-8199 has potential as a radioligand in human PET studies using models where a slow metabolism is an advantage.
Received 19 April and in revised form 10 June 1997 相似文献
20.
Cardiovascular malformations, work attendance, and occupational exposures during pregnancy in Finland 总被引:1,自引:0,他引:1
J Tikkanen K Kurppa H Timonen P C Holmberg E Kuosma K Rantala 《American journal of industrial medicine》1988,14(2):197-204
To explore for associations between occupational factors and cardiovascular malformations, information on the parents of 160 infants with cardiovascular malformations and 160 control parents was studied. The case infants had been reported consecutively to the Finnish Register of Congenital Malformations. All mothers were interviewed identically after delivery, using both open and pro forma questions about detailed work tasks, exposures, and leisure activities during pregnancy. The interview information was evaluated blindly. Neither parental occupational titles nor maternal working per se gave new clues to the teratogenic risk; nor did shift working, wearing of personal protective equipment, or the mother's own opinion on exposures during pregnancy. Identified occupational exposures, as categorized by an industrial hygienist, showed no remarkable associations to cardiovascular malformations. Few mothers were exposed substantially to specific occupational hazards. Comparing mothers who used medications in the first trimester with those who did not showed an odds ratio of 2.2 (95% confidence interval 1.3-3.9) when adjusted for potential confounding by multivariate logistic methods. 相似文献